Résumé | The consensus problem in anonymous,
failures prone and asynchronous shared memory systems is investigated. A
new class of failure detectors, called
anonymity-preserving
failure detectors suited to anonymous systems is introduced. As its name indicates, a failure
detector in this class cannot be relied upon to break anonymity. For example, the anonymous perfect detector
AP
, which gives at each process
an estimation of the number of processes that have failed belongs to this
class.
The weakest failure detector among this class for consensus is then determined. This failure detector, called
C
, may be seen as a loose
failures counter: (1) after a failure occurs, the counter is eventually in-
cremented, and (2) if two or more processes are non-faulty, it eventually
stabilizes.
Joint work with Zohir Bouzid |